Is it any specific language? The people themselves and their culture seem to be intentionally generic.
I'm sorry if I'm late, but I do confirm there is a part of Indonesian/Malay language. I wasn't looking at the subtitles when I began a new game, and I immediately recognized the language when the narrator spoke, but it is indeed mixed with another language, probably Swahili like Samthere stated.
Source : myself, I'm not an Indonesian but I've lived there for 3 years, so I can speak some basics